A doctor will perform a physical exam when he or she suspects that a baby or child has cystic fibrosis. Usually, symptoms of cystic fibrosis appear during infancy or early childhood. During the exam, the doctor may:

• Listen to the child's heart and lungs with a stethoscope to find out if mucus is clogging breathing passages.
• Take the child's temperature, pulse, blood pressure, height, and weight. If a child is not gaining weight at a normal rate and has other symptoms, such as frequent lung infections or greasy stools, cystic fibrosis may be suspected.
• Feel the stomach for an enlarged liver, swollen belly, or firm lumps, particularly on the right side of the body.
• Look at the fingers for thickening and rounding of the fingertips (clubbing) or curving of the fingernails. This may mean the child has respiratory problems.
• Look inside the nose for nasal polyps.

A physical exam alone will not diagnose cystic fibrosis. The doctor will also consider the child's risk factors and test results before making a diagnosis of cystic fibrosis.

If cystic fibrosis is first suspected in adulthood, it is usually because symptoms are mild.